Weather

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fxus63 kind 071142 
afdind 


Area forecast discussion 
National Weather Service Indianapolis in 
735 am EDT sun Sep 7 2008 


Aviation discussion...for the 12z tafs 
VFR conditions through the taf period. A weak cold front was just 
north of the Ohio River at the beginning of the tafs. This will 
continue to move east. There is limited moisture with this system. 
Very scattered showers were behind the front. These will have little 
effect on visibility and should be out of taf locations by 16z. The ac 
west of the front will move through Indiana during the morning. This 
afternoon only scattered cumulus and ac will occur. Some ac will move back into 
Indiana toward end of tafs ahead of next system. 


&& 


Discussion...forecast focus will be on next chance of rain. 


Today and tonight...high pressure will continue over central Indiana 
today. A short wave was pushing through northern Illinois into 
northern Indiana resulting in an area of showers. Some of these 
showers were reaching the far northwest portion of the County Warning Area and may have to 
make mention of these in the first few hours of the forecast period. 
Otherwise extensive cloud cover will keep skies cloudy for most of 
the day. That coupled with 850 mb cold advection will keep temperatures below 
normal once again today. Will lean toward cooler MOS for the 
aforementioned reasons. Tonight skies will clear out allowing temperatures 
to drop into the middle to upper 50s. 


Monday and Monday night...a developing surface low near the 4 corners 
region will push a warm front into the County Warning Area on Monday. The NAM/GFS 
are not in good agreement with timing...placement or quantitative precipitation forecast with this 
system. With the frontal boundary in place and an increasing 850 mb 
jet on Monday night will continue with chance probability of precipitation most areas but 
expand the likely area a little farther south as the surface wave 
will help along any rain showers/thunderstorms and rain to develop. A cold front will move 
through in the wake of the surface wave further increasing chances for 
precipitation late Monday. Temperatures on Monday could be tricky as the 
placement of the front will determine which areas are warmer and in 
the middle 80s and which areas are cooler. Will keep the far South County warning area 
in the middle 80s range then gradually lower highs farther north. 


Tuesday and Wednesday...high pressure will return Tuesday and Wednesday with 
dry conditions expected. Temperatures will return to below normal readings 
which is now around 80 for this time of year. 


From Thursday on precipitation chances will hinge on the eventual track of 
Ike. European model (ecmwf) tries to bring a cold front through on Thursday night 
but this could end up faster or slower depending upon Ike. For now 
will leave things as is with such high uncertainty. 


&& 


Ind watches/warnings/advisories...none. 


$$ 
Public...Sally 
aviation...sh